They run out at about 40 stone/iron/wood/herbs, which as sling said, is one stam bar. I'll copy-paste my gathering macro in a second, but you have to babysit your character a little bit. I mean, a stam bar runs out in probably 5-10 minutes of gathering, so you can watch a movie and just switch nodes every once in a while, but it's not like you can just go to work and stay gathering. You also break a pickaxe after about 3-5 stam bars.

BoS Archon
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